A test device for simulating hydrology and water quality of slope protection structure

Abstract

The present invention discloses a test device for simulating the hydrology and water quality of a slope protection structure. The test device includes a water supply tank, a rectifying trough, a test chamber and a stratified water collector. The test chamber is arranged obliquely, the rectifying trough is arranged at the entrance of the upper boundary of the test chamber, the outlet of the rectifying trough is arranged with an overflow weir, and the stratified water collector is arranged at the outlet of the lower boundary of the test chamber. The stratified water collector includes a water collecting box, a water-blocking layer, a surface water outlet pipe and a groundwater water outlet pipe. The water collecting box is connected to the test chamber, the water-blocking layer divides the water collecting box into two upper and lower cavities, the surface water outlet pipe is connected to the upper cavity in the water collecting box, and the groundwater water outlet pipe is connected to the lower cavity in the water collecting box. The water inlet adopts a rectifying trough with an overflow weir and the water outlet adopts a stratified water collection design. The overflow water inlet simulates the water coming from the road and the surrounding environment. The stratified water collection is used to monitor the water quality and water quantity changes of surface water and groundwater respectively, and the test effect of real simulation is achieved. The present invention can be widely used in the field of water conservancy engineering technology.

Description

Technical Field

[0001] The invention relates to the technical field of water conservancy engineering, and in particular to a test device for simulating the hydrology and water quality of a slope protection structure. Background Art

[0002] Runoff pollution control is one of the four major control targets of sponge city construction. Ecological slope protection is the last line of defense for surface runoff pollution entering the river. It is also an important space for achieving river water purification and an important channel for mutual infiltration and replenishment of surface water and groundwater. After rainwater runoff enters the slope protection structure, it is intercepted and retained by surface vegetation, infiltrated and adsorbed by soil, absorbed and degraded by plant roots, and other physical and chemical effects, resulting in material and energy conversion. The process mechanism is very complex and it is difficult to perform systematic simulation calculations with the help of mathematical models. Physical model testing is the most effective scientific means to quantitatively evaluate the effect of ecological slope protection on runoff pollution control and to study and test the optimization of slope protection structure combinations. The scientific rationality of the design of physical model test equipment directly affects the success or failure of scientific experiments and the reliability of test results.

[0003] The role of ecological slope protection in controlling runoff pollution is mainly the combined effects of vegetation and its root interception and degradation absorption, soil and slope protection structural materials penetration and adsorption. The hydrological and water quality test device simulating the slope protection structure must have the functions of runoff simulation monitoring at the upper boundary entrance of the slope protection, the middle section slope protection structure test chamber, the lower boundary outlet flow monitoring and water quality sampling.

[0004] At present, there are very few studies on hydrological and water quality simulation tests of slope protection structures at home and abroad. In the literature, slope protection test devices with a combination of spray water supply and experimental chambers are generally used. Similar research devices include permeable pavement test devices, rain garden tests and other sponge city measures related test devices. However, the above test devices all have certain limitations. For example, the use of spraying to simulate the outer boundary rainwater runoff and the way it carries pollutants into the test area is different from the actual overflow entry method, which will lead to water volume, spatial distribution of pollutants and concentration gradient field being different from the actual situation; common devices only use a unified outlet at the outlet boundary to collect water volume or water quality sampling, and do not subdivide surface water and groundwater for separate monitoring and detection. The monitoring results cannot distinguish the differences in the hydrological and water quality transformation processes of different materials and boundary conditions on the surface and underground, which is not conducive to the in-depth analysis of research results.

[0005] Therefore, developing reasonable simulation devices in order to achieve the effect of truly simulating the hydrological and water quality changes on the slope protection structure is of great significance for conducting relevant scientific research on the retention and purification effects of slope protection structures on rainwater runoff and the pollutants it carries. Summary of the invention

[0006] In order to solve at least one of the above technical problems and achieve the effect of truly simulating the hydrological and water quality changes on the slope protection structure, the present invention provides a test device for simulating the hydrological and water quality of the slope protection structure. The technical solution adopted is as follows:

[0007] The test device for simulating the hydrology and water quality of the slope protection structure provided by the present invention includes a water supply tank, a rectifying trough, a test chamber and a stratified water collector. The test chamber is arranged at an angle, the rectifying trough is arranged at the inlet of the upper boundary of the test chamber, the outlet of the rectifying trough is arranged with an overflow weir, and the stratified water collector is arranged at the outlet of the lower boundary of the test chamber. The stratified water collector includes a water collecting tank, a waterproof layer, a surface water outlet pipe and a groundwater outlet pipe. The water collecting tank is connected to the test chamber, the waterproof layer divides the water collecting tank into two upper and lower cavities, the surface water outlet pipe is connected to the upper cavity in the water collecting tank, and the groundwater outlet pipe is connected to the lower cavity in the water collecting tank.

[0008] Furthermore, the test chamber includes a geotextile, a plain soil layer, a geonet, a plain soil layer, a slope protection material layer, a planting soil layer and slope protection vegetation arranged in layers from bottom to top.

[0009] Furthermore, at the exit of the test chamber, the planting soil layer is located higher than the waterproof layer.

[0010] Furthermore, a soil moisture monitoring instrument is arranged in the test chamber.

[0011] Furthermore, the upper and lower cavities of the water collecting tank are respectively provided with filter layers.

[0012] Furthermore, the filter layer is filled with fine sand, coarse sand and gravel in sequence along the water flow direction.

[0013] Furthermore, the waterproof layer is funnel-shaped, and the surface water outlet pipe is arranged at the lowest position of the waterproof layer.

[0014] Furthermore, the bottom wall of the water collecting tank is funnel-shaped, and the groundwater outlet pipe is arranged at the lowest position of the bottom wall of the water collecting tank.

[0015] Furthermore, a pressure pump is arranged between the water supply tank and the rectifying tank.

[0016] Furthermore, a flow meter is arranged between the water supply tank and the rectifying tank.

[0017] The embodiments of the present invention have at least the following beneficial effects: in the test device, the water inlet adopts a rectifying trough with an overflow weir and the water outlet adopts a stratified water collection design, the overflow water inlet simulates the water coming from the road and the surrounding environment, and the stratified water collection is used to monitor the water quality and quantity changes of surface water and groundwater respectively, which has a real simulation test effect. The present invention can be widely used in the field of water conservancy engineering technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a side view of the structure of the test device, in which the arrows indicate the direction of water flow;

[0019] Figure 2 It is the structural schematic diagram of the rectifier tank;

[0020] Figure 3 This is a schematic diagram of the structure of the stratified water collector, in which the arrows indicate the direction of water flow. DETAILED DESCRIPTION

[0021] Combine the following Figures 1 to 3 The present invention is further described.

[0022] The present invention relates to a test device for simulating the hydrology and water quality of a slope protection structure. The test device comprises a water supply tank 11, a rectifying trough 12, a test chamber 13 and a stratified water collector. The test chamber 13 is arranged obliquely, the rectifying trough 12 is arranged at the inlet of the upper boundary of the test chamber 13, and the stratified water collector is arranged at the outlet of the lower boundary of the test chamber 13.

[0023] The rectifier tank 12 is connected to the water supply tank 11 through a water supply pipe. In some embodiments, a booster pump is arranged between the water supply tank 11 and the rectifier tank 12. In some embodiments, a flow meter is arranged between the water supply tank 11 and the rectifier tank 12. The test device uses the water supply tank 11, a booster pump, a water supply pipe, an electromagnetic valve and a flow meter, a PC controller, etc. to form a water supply system to deliver a water sample of a required concentration to the rectifier tank 12.

[0024] The rectifying trough 12 is used to realize rectifying buffering, and an overflow weir 14 is arranged at the outlet of the rectifying trough 12, and the overflow weir 14 is a thin-walled structure. The runoff enters the test chamber 13 by overflow, simulating the confluence of surface runoff, and completes the natural hydrological processes such as slope confluence, infiltration and groundwater confluence in the test chamber 13. Before the start of the test, clean water needs to be injected to test the rectifying trough 12 to test whether the top of the overflow weir 14 is horizontal and whether the overflow is laterally uniform. Through the hydrological processes such as natural confluence and infiltration of the test chamber 13, accompanied by the physical and chemical effects of interception, filtration, adsorption, and degradation of substances, surface runoff and underground runoff are formed at the lower boundary of the test chamber 13.

[0025] The test device optimized the water inlet method. Considering that the natural rainfall and the total amount of pollutants carried in the area above the slope protection structure are relatively small, a large amount of rainwater runoff and pollutants in the slope protection structure mainly come from the catchment areas such as embankments and surrounding roads, and enter the slope protection structure through confluence or overflow. Therefore, the rectification water tank and natural overflow method are used to more realistically simulate the process of natural rainwater runoff entering the slope protection test section.

[0026] The test chamber 13 includes geotextile, soil layer, geonet, soil layer, slope protection material layer, soil layer and slope protection vegetation arranged in layers from bottom to top. To ensure the water balance of the test, the bottom and side walls of the test chamber 13 are waterproof, and a soil moisture monitoring instrument is arranged in the test chamber 13 to monitor the soil moisture content before and after the test.

[0027] The outlet of the test chamber 13 is optimized as a layered design. The layered water collector includes a water collecting box, a water-blocking layer 15, a surface water outlet pipe 16 and a groundwater outlet pipe 17. The water collecting box is connected to the test chamber 13. The water-blocking layer 15 divides the water collecting box into two upper and lower cavities, which are used to collect surface water and groundwater respectively. The surface water and groundwater generated by the test are collected separately through the layered water collector, so as to realize the synchronous observation of the hydrology and water quality of surface water and groundwater.

[0028] The surface water outlet pipe 16 is connected to the upper cavity in the water collecting box, the water barrier 15 is funnel-shaped, and the surface water outlet pipe 16 is arranged at the lowest position of the water barrier 15 to ensure smooth drainage. The groundwater outlet pipe 17 is connected to the lower cavity in the water collecting box, the bottom wall of the water collecting box is funnel-shaped, and the groundwater outlet pipe 17 is arranged at the lowest position of the bottom wall of the water collecting box to ensure smooth drainage.

[0029] At the outlet of the test chamber 13, the position of the planting soil layer is higher than the waterproof layer 15, so that the surface water flows into the cavity above the waterproof layer 15 in the water collection tank.

[0030] After the rainwater runoff enters the slope protection structure, part of it flows downward along the slope protection surface under the action of gravity, and the other part penetrates into the soil through the gaps in the slope protection materials, soil, etc. to form underground runoff. The pollutants it carries also follow the flow of water and disperse into the slope protection surface and soil. Among them, solid suspended matter with larger particles is easily intercepted by the vegetation on the slope protection surface, while soluble substances (such as phosphates, etc.) penetrate into the soil with surface runoff and are adsorbed by the soil or absorbed by the plant roots. Therefore, when the conditions such as the slope protection structure material, vegetation type, and slope size are different, there are large differences in water volume ratio, water quality concentration change, etc. between surface runoff and underground runoff, and they need to be monitored and evaluated separately. For this reason, a water-proof layer 15 is set at the foot of the slope at the lower edge of the slope protection structure, and a water collection permeability system of surface water and groundwater stratification is adopted to achieve the purpose of the test device being able to monitor and collect surface water and groundwater separately.

[0031] In order to avoid soil scouring at the outlet of the test chamber 13, the upper and lower cavities of the water collecting tank are respectively provided with filter layers, and the filter layers are filled with fine sand, coarse sand and gravel in sequence along the water flow direction.

[0032] The design idea of ​​the test device is as follows: the inlet of the test chamber 13 adopts the overflow method of the rectifier trough 12 to let in water, the bottom and side walls of the test chamber 13 are sealed and waterproofed to ensure the water balance of the test, and the outlet of the test chamber 13 adopts a layered filtration water collection structure to collect surface water and groundwater flowing out of the test chamber 13 respectively, and monitor the water volume and quality to ensure that the test process is as close as possible to the actual hydrological and water quality changes of the slope protection structure. The test device can distinguish the different hydrological and water quality changes of surface water and groundwater, so that the experimental research can objectively reflect the actual hydrological and water quality changes on the slope protection structure.

[0033] The test device is structurally divided into a water supply system, a water distribution and rectification system, a filling bin and a stratified water collection system, which realizes the functions of inlet rectification and outlet surface runoff, groundwater stratification detection, measurement and adoption. It has good support for studying the laws of surface preparation and soil matrix purification of water pollutants, vertical penetration of runoff, etc., and is suitable for simulation tests of different slope protection materials.

[0034] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the technical field without departing from the purpose of the present invention.

Claims

1. A test device for simulating the hydrology and water quality of a slope protection structure, characterized in that: The invention comprises a water supply tank (11), a rectifying trough (12), a test chamber (13) and a stratified water collector, wherein the test chamber (13) is arranged obliquely, the rectifying trough (12) is arranged at the inlet of the upper boundary of the test chamber (13), an overflow weir (14) is arranged at the outlet of the rectifying trough (12), the weir top of the overflow weir (14) is arranged horizontally to make the overflow uniform in the transverse direction, and the stratified water collector is arranged at the outlet of the lower boundary of the test chamber (13), the stratified water collector comprises a water collecting box, a water-blocking layer (15), a surface water outlet pipe (16) and a groundwater water outlet pipe (17), the water collecting box is connected to the test chamber (13), the water-blocking layer (15) divides the water collecting box into two upper and lower cavities, the surface water outlet pipe (16) is connected to the upper cavity in the water collecting box, and the groundwater outlet pipe (17) is connected to the lower cavity in the water collecting box.

2. The test device for simulating hydrology and water quality of slope protection structure according to claim 1 is characterized by: The test chamber (13) comprises a geotextile, a plain soil layer, a geonet, a plain soil layer, a slope protection material layer, a planted soil layer and slope protection vegetation arranged in layers from bottom to top.

3. The test device for simulating hydrology and water quality of slope protection structure according to claim 2 is characterized by: At the outlet of the test chamber (13), the position of the planting soil layer is higher than the waterproof layer (15).

4. The test device for simulating hydrology and water quality of slope protection structure according to claim 1 is characterized by: A soil moisture monitoring instrument is arranged in the test chamber (13).

5. The test device for simulating hydrology and water quality of slope protection structure according to claim 1 is characterized by: The upper and lower cavities of the water collecting box are respectively provided with reverse filter layers.

6. The test device for simulating hydrology and water quality of slope protection structure according to claim 5 is characterized by: The filter layer is filled with fine sand, coarse sand and gravel in sequence along the water flow direction.

7. The test device for simulating hydrology and water quality of slope protection structure according to claim 1 is characterized by: The waterproof layer (15) is funnel-shaped, and the surface water outlet pipe (16) is arranged at the lowest position of the waterproof layer (15).

8. The test device for simulating hydrology and water quality of slope protection structure according to claim 1 is characterized by: The bottom wall of the water collecting tank is funnel-shaped, and the groundwater outlet pipe (17) is arranged at the lowest position of the bottom wall of the water collecting tank.

9. The test device for simulating hydrology and water quality of slope protection structure according to claim 1, characterized in that: A pressure pump is arranged between the water supply tank (11) and the rectifying tank (12).

10. The test device for simulating hydrology and water quality of slope protection structure according to claim 1, characterized in that: A flow meter is arranged between the water supply tank (11) and the rectifying tank (12).

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